1. Field of the Invention
The invention relates to a protection device, and more particularly to an electrostatic discharge (ESD) protection device.
2. Description of the Related Art
Generally, each integrated circuit (IC) comprises at least one input terminal and at least one output terminal. When the input terminal receives high voltage electrostatic charges and the output terminal is grounded, the electrostatic charges passes through the IC and is released to the ground. The release process is referred to as an ESD event. The ability of electrostatic discharge is not plenty. However, ESD energy is great due to the high voltage. If the electrostatic discharge is not processed, the IC will be damaged.
As semiconductor manufacturing evolves, ESD protection has become one of the most critical reliability issues for integrated circuits (IC). Several ESD test modes, such as machine mode (MM) or human body mode (HBM), have been proposed to imitate the circumstances under which an ESD event may occur. The ability to withstand certain ESD levels is essential for successful commercialization of ICs.